Currently have 525 chain and sprockets on my bike. Chain needs replacing. When I purchased the bike the guy included new 520 sprockets and 520 chain that were not installed. Should I just swap it all to 520 or just buy 525 chain and sell the sprockets and chain? What are pro/cons of each?

If you didn't have the 520 chain and sprockets already I would've stayed with the 525 but hell its free so you might as well use it. I'm not nearly good enough to take any advantage of weight loss in the 525 to 520 chain conversion. I'd much rather have the beefier chain.

__________________06 CBR600F4I
09 CBR600RR
01 750 Shadow

The Following User Says Thank You to Pennywisdomj For This Useful Post:

Might as well use up the 520. When you need to purchase a chain kit though there is no reason not to get a 520. The question is if you want a alum or steel rear sprocket. The modern high end chains and a steel rear sprocket will last longer then a mediocre 525 chain kit and weigh less and cost less. There really isn't any reason not to go 520 on a 600cc bike anymore.

Might as well use up the 520. When you need to purchase a chain kit though there is no reason not to get a 520. The question is if you want a alum or steel rear sprocket. The modern high end chains and a steel rear sprocket will last longer then a mediocre 525 chain kit and weigh less and cost less. There really isn't any reason not to go 520 on a 600cc bike anymore.

Well 525 is a bit wider then 520. Not much, but a hair. However, remember that not all chain kits are created equal. That is what people forget. The stock chain is mass produced and the chain is nowhere near as strong as the aftermarket products that are the equivalent. For example the stock 525 chain won't last nearly as long as the ek zzz 525 or ek mvxz 525 as it's a much better quality. Bikes are mass produced and they need to keep the costs down.

Now, a chain kit (front sprocket, rear sprocket, and chain) are only as strong as their weakest link. All front sprockets are steel and super strong. A rear sprocket can be alum or steel. The chain is steel.

So if you get an alum rear sprocket that is your weak link so you don't needa super super strong chain. However, if you get a steel rear sprocket then the chain is the weak link. So then you get a super strong chain like the ek mvxz or ek zzz and you have a 520 about as strong as the stock 525 chain.

The chain kit will last just as long as it's a better product, it's less weight, and less money. It's just better technology.

The thing people forget is that the quality of the products makes a huge difference. Now if you take the same steel sprockets and an ek zzz chain 525 sure it's a bit stronger then the 520 as it's the same products, but it's over kill for a 600cc bike. Reason being is that not only does abuse destroy a chain kit, but so does time and the elements/weather. If you have a chain kit for say 4 years and only have 2k miles on it I would wager the chain is in very bad shape due to humidity, moisture, etc. I would say the chain likely has rust and is beat up as well. Not by use, but by the time and weather from sitting there. So there is no need on a 600cc bike to run a 525 or 530 UNLESS it's a 100% stunt bike (tons of abuse) or you have a turbo, built engine, etc and are pushing upwards of 200hp to the wheel out of the bike. Then, sure, get a 525 or 530 chain kit.

So with these new superlight steel 520 rear sprockets and the already super strong chain technology that is out there for 99% of 600cc rides there is no reason not to get a 520 chain kit. The only question to ask is "should I get a superlight steel rear sprocket or hard anodized alum" and the answer to that depends on if you want longevity or light weight. The superlight steel rear sprockets weight about 1lb more then the hard anodized alum. Not a lot too notice, but if you're racing or it's a track bike you would probably want the hard anodized alum rear sprocket. If it's a street bike you would probably want the superlight steel rear sprocket like the Driven Evo-Spec superlight steel chain kit we sell.

Well 525 is a bit wider then 520. Not much, but a hair. However, remember that not all chain kits are created equal. That is what people forget. The stock chain is mass produced and the chain is nowhere near as strong as the aftermarket products that are the equivalent. For example the stock 525 chain won't last nearly as long as the ek zzz 525 or ek mvxz 525 as it's a much better quality. Bikes are mass produced and they need to keep the costs down.

Now, a chain kit (front sprocket, rear sprocket, and chain) are only as strong as their weakest link. All front sprockets are steel and super strong. A rear sprocket can be alum or steel. The chain is steel.

So if you get an alum rear sprocket that is your weak link so you don't needa super super strong chain. However, if you get a steel rear sprocket then the chain is the weak link. So then you get a super strong chain like the ek mvxz or ek zzz and you have a 520 about as strong as the stock 525 chain.

The chain kit will last just as long as it's a better product, it's less weight, and less money. It's just better technology.

The thing people forget is that the quality of the products makes a huge difference. Now if you take the same steel sprockets and an ek zzz chain 525 sure it's a bit stronger then the 520 as it's the same products, but it's over kill for a 600cc bike. Reason being is that not only does abuse destroy a chain kit, but so does time and the elements/weather. If you have a chain kit for say 4 years and only have 2k miles on it I would wager the chain is in very bad shape due to humidity, moisture, etc. I would say the chain likely has rust and is beat up as well. Not by use, but by the time and weather from sitting there. So there is no need on a 600cc bike to run a 525 or 530 UNLESS it's a 100% stunt bike (tons of abuse) or you have a turbo, built engine, etc and are pushing upwards of 200hp to the wheel out of the bike. Then, sure, get a 525 or 530 chain kit.

So with these new superlight steel 520 rear sprockets and the already super strong chain technology that is out there for 99% of 600cc rides there is no reason not to get a 520 chain kit. The only question to ask is "should I get a superlight steel rear sprocket or hard anodized alum" and the answer to that depends on if you want longevity or light weight. The superlight steel rear sprockets weight about 1lb more then the hard anodized alum. Not a lot too notice, but if you're racing or it's a track bike you would probably want the hard anodized alum rear sprocket. If it's a street bike you would probably want the superlight steel rear sprocket like the Driven Evo-Spec superlight steel chain kit we sell.

Do you have a steel rear sprocket or alum? If it's an alum rear sprocket that is your weak link so any top end chain from did, ek, or rk will be fine.

If you have a steel rear sprocket then I would go with the ek mvxz, ek zzz, or rk gxw as they are stronger. Not too mention they cost less then the did. I would run ek or rk over did regardless due to the price. If you're racing then the did is a bit less weight (like 3 ounces) so it may help if you need to win by like .002 seconds compared to 2nd place. On the street you won't notice the difference so why not save money and go with the ek or rk as they are stronger and cost less. :)

Well 525 is a bit wider then 520. Not much, but a hair. However, remember that not all chain kits are created equal. That is what people forget. The stock chain is mass produced and the chain is nowhere near as strong as the aftermarket products that are the equivalent. For example the stock 525 chain won't last nearly as long as the ek zzz 525 or ek mvxz 525 as it's a much better quality. Bikes are mass produced and they need to keep the costs down.

Now, a chain kit (front sprocket, rear sprocket, and chain) are only as strong as their weakest link. All front sprockets are steel and super strong. A rear sprocket can be alum or steel. The chain is steel.

So if you get an alum rear sprocket that is your weak link so you don't needa super super strong chain. However, if you get a steel rear sprocket then the chain is the weak link. So then you get a super strong chain like the ek mvxz or ek zzz and you have a 520 about as strong as the stock 525 chain.

The chain kit will last just as long as it's a better product, it's less weight, and less money. It's just better technology.

The thing people forget is that the quality of the products makes a huge difference. Now if you take the same steel sprockets and an ek zzz chain 525 sure it's a bit stronger then the 520 as it's the same products, but it's over kill for a 600cc bike. Reason being is that not only does abuse destroy a chain kit, but so does time and the elements/weather. If you have a chain kit for say 4 years and only have 2k miles on it I would wager the chain is in very bad shape due to humidity, moisture, etc. I would say the chain likely has rust and is beat up as well. Not by use, but by the time and weather from sitting there. So there is no need on a 600cc bike to run a 525 or 530 UNLESS it's a 100% stunt bike (tons of abuse) or you have a turbo, built engine, etc and are pushing upwards of 200hp to the wheel out of the bike. Then, sure, get a 525 or 530 chain kit.

So with these new superlight steel 520 rear sprockets and the already super strong chain technology that is out there for 99% of 600cc rides there is no reason not to get a 520 chain kit. The only question to ask is "should I get a superlight steel rear sprocket or hard anodized alum" and the answer to that depends on if you want longevity or light weight. The superlight steel rear sprockets weight about 1lb more then the hard anodized alum. Not a lot too notice, but if you're racing or it's a track bike you would probably want the hard anodized alum rear sprocket. If it's a street bike you would probably want the superlight steel rear sprocket like the Driven Evo-Spec superlight steel chain kit we sell.

Any other questions just ask :)

Question for you, MM. Your site is pretty informative regarding chains and gearing, but just for confirmation, can I use a 520 chain with my OEM gearing (16/42 - 07 600rr)? My main fear is messing up the speedometer accuracy, but I know that's only possible when changing out sprockets. I know when you change up sprockets it influences top speed as well. None of that will happen if I merely put a 520 chain on, correct? I love OEM gearing and don't want to lose any of those properties, but I'd love to have a lighter chain and shed rotational weight off

I always wondered where the number "520" or "525" came from. I know it refers to "pitch", but still curious were the actual number comes from. Is it a measurement of some sort?

+1 thx: Not all 520 chain kits are strong either. We only sell the best of all the sprocket brands out there and the chain brands for this reason. There are cheaper chain kits out there, but you'll surely get cheaper quality. We drop brands the minute we feel they are no longer a top tier brand as well. ek, rk, did make lots of chains, but only sell their best chains. With the power these bikes are putting down we feel the chain kit is no place to skimp out or you could end up stranded, with a chain going through your engine, or even your foot. Just not worth it.

Well 525 is a bit wider then 520. Not much, but a hair. However, remember that not all chain kits are created equal. That is what people forget. The stock chain is mass produced and the chain is nowhere near as strong as the aftermarket products that are the equivalent. For example the stock 525 chain won't last nearly as long as the ek zzz 525 or ek mvxz 525 as it's a much better quality. Bikes are mass produced and they need to keep the costs down.

Now, a chain kit (front sprocket, rear sprocket, and chain) are only as strong as their weakest link. All front sprockets are steel and super strong. A rear sprocket can be alum or steel. The chain is steel.

So if you get an alum rear sprocket that is your weak link so you don't needa super super strong chain. However, if you get a steel rear sprocket then the chain is the weak link. So then you get a super strong chain like the ek mvxz or ek zzz and you have a 520 about as strong as the stock 525 chain.

The chain kit will last just as long as it's a better product, it's less weight, and less money. It's just better technology.

The thing people forget is that the quality of the products makes a huge difference. Now if you take the same steel sprockets and an ek zzz chain 525 sure it's a bit stronger then the 520 as it's the same products, but it's over kill for a 600cc bike. Reason being is that not only does abuse destroy a chain kit, but so does time and the elements/weather. If you have a chain kit for say 4 years and only have 2k miles on it I would wager the chain is in very bad shape due to humidity, moisture, etc. I would say the chain likely has rust and is beat up as well. Not by use, but by the time and weather from sitting there. So there is no need on a 600cc bike to run a 525 or 530 UNLESS it's a 100% stunt bike (tons of abuse) or you have a turbo, built engine, etc and are pushing upwards of 200hp to the wheel out of the bike. Then, sure, get a 525 or 530 chain kit.

So with these new superlight steel 520 rear sprockets and the already super strong chain technology that is out there for 99% of 600cc rides there is no reason not to get a 520 chain kit. The only question to ask is "should I get a superlight steel rear sprocket or hard anodized alum" and the answer to that depends on if you want longevity or light weight. The superlight steel rear sprockets weight about 1lb more then the hard anodized alum. Not a lot too notice, but if you're racing or it's a track bike you would probably want the hard anodized alum rear sprocket. If it's a street bike you would probably want the superlight steel rear sprocket like the Driven Evo-Spec superlight steel chain kit we sell.

Any other questions just ask :)

This is very informative and helpful. this clearified my confusion with chains kits and gives me confidence in the 520 chain.

Reviving an old thread as I'm currently doing my research for a new chain(I'm at 16.5k on the original) and it looks like I should go with a 520, steel front/rear and the EK MVXZ.

My question is what is the average longevity difference b/w the MVXZ and 3D?

I see there's a 400lb difference in tensile strength on Motomummy's page, yet I'm wondering what this translates to in avg mileage w/ no stunting and regular 500mi cleaning/lube. For reference my stock 525 is at 16.5k and I'm hoping it would last 20k, but don't want to risk it.

Also, should I go for -1/+2? I don't plan on doing any top speed runs so acceleration and a smooth power band in the usable range is more important to me, lol, if I wanted top speed I would've got a 'busa.

Finally, are there any warning signs when I chain is about to snap? Aside from the swingarm marks, is there something to look out for that means "oh crap, don't ride this thing until I get a new chain!"